Compression dynamics of forward and backward gaussian pulses in a cascaded optical guide

The dynamics of a Gaussian pulse propagating in the forward or backward direction in a linear cascaded optical guide consisting of a sequence of active (with amplification) and passive elements whose dispersion parameters are assumed to be known is studied. Conditions for pulse compression in a cascaded guide are analyzed. The influence of the accompanying effect of the carrier-frequency shift on this process and the possibility of propagation of the maximum of the wave-packet envelope at a speed higher than the velocity of light in vacuum is considered.